I question the relevancy of that article from Forbes regarding Windows Phone. It is written by a Contributor, so it is basically an editorial piece. The sentence "Nokia becomes a low-end smartphone-maker" strikes me as particularly weird, as Nokia was always a low-end phone maker.

While their sales are down in the US, they are on a (very slow) rise almost everywhere else. In Latin America, WP is now ranked 2nd (http://techcrunch.com/2013/08/22/windows-phone-snags-second-...).

WP is definitely not a widely successful platform, but it is not yet a total failure, and given some more attention from Microsoft, it may yet succeed in being relevant.

edited for typos.